Bridge strike reduction: the design and evaluation of visual warnings

The aim of this investigation was to consider the problem of road vehicles that strike rail-over-road bridges and how such incidents can be reduced. In particular, it examined the design of both the warning markings placed on bridges and the road signs situated some distance in front of the bridge, each warning of reduced clearances ahead. Initially, a literature review was conducted to reveal the nature of the problem, including the history of bridge strikes, previous attempts to quantify why bridges are hit, the cost of strikes, countermeasures to prevent them and the legal restrictions relevant to the area. It was concluded that no single countermeasure had been found to be effective when the cost and the legal restrictions were taken into account.A field assessment of possible causal factors was performed in order to compare a group of bridges that had been frequently struck, against a group of control bridges. It was found that frequently struck bridges generally were in busier environments (as might be expected), and in more visually complex environments where there were, on average, more advertisements nearby - thus more potential distractions were present at these sites. The research then considered what drivers look at when driving towards low bridges,specifically focusing on the amount of visual attention given to warning signs prior to a low bridge, and on the specific areas drivers look at in the final few seconds before reaching the bridge. It was found that the bridge warning signs and bridge markings performed badly on measures of visual attention. In addition, if an advertisement was placed on the top section of a bridge, this was looked at for a large proportion of the time - thus reducing the proportion of time which the drivers gave to other features of the environment. The development and evaluation of alternative bridge warning signs was then considered. Newly created and existing signs were evaluated on tests of comprehension and hazard perception. The results demonstrated that text-based versions of the warning sign with a yellow border performed best The development and evaluation of markings for low bridges were then examined by evaluating newly created and existing markings. The research focussed on their capacity to make a bridge appear lower than it really was - so influencing drivers' judgement of height when they approach such a bridge. The current low bridge marking standard achieved inferior scores on the experimental measures employed when compared to several of the alternative bridge marking designs that were developed. Finally, the investigation examined driver responses to both the bridge signs and markings. Using a virtual reality road scene, an experiment was performed which assessed if the existing and modified designs of the signs and markings identified earlier had any behavioural effects upon drivers as they approached the 'virtual' bridges. The addition of warning signs before the bridge was found to have no significant influence on subjects' decisions regarding stopping before the bridge. However, the type of markings displayed on the bridge did significantly affect their responses

Development assistance and the environment : a question of accountability

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 1985.MICROFICHE COPY AVAILABLE IN ARCHIVES AND ROTCH.Bibliography: leaves 387-401.by John Alfred James Horberry.Ph.D

Cholesteric Liquid Crystal Shells as Enabling Material for Information-Rich Design and Architecture.

The responsive and dynamic character of liquid crystals (LCs), arising from their ability to self-organize into long-range ordered structures while maintaining fluidity, has given them a role as key enabling materials in the information technology that surrounds us today. Ongoing research hints at future LC-based technologies of entirely different types, for instance by taking advantage of the peculiar behavior of cholesteric liquid crystals (CLCs) subject to curvature. Spherical shells of CLC reflect light omnidirectionally with specific polarization and wavelength, tunable from the UV to the infrared (IR) range, with complex patterns arising when many of them are brought together. Here, these properties are analyzed and explained, and future application opportunities from an inter- disciplinary standpoint are discussed. By incorporating arrangements of CLC shells in smart facades or vehicle coatings, or in objects of high value subject to counterfeiting, game-changing future uses might arise in fields spanning infor- mation security, design, and architecture. The focus here is on the challenges of a digitized and information-rich future society where humans increasingly rely on technology and share their space with autonomous vehicles, drones, and robots

Forklift safety, traffic engineering and intelligent transport systems: a case study

This paper details a previous termforklift safetynext term demonstration project undertaken at two manufacturing sites in Victoria, Australia. The purpose of the work was both to help improve previous termsafetynext term at the two sites, and, more broadly, to develop, help implement and evaluate a series of human-centred design interventions involving vehicles and pedestrian workers. The ‘before’ and ‘after’ case study presented here summarises the background to the research and introduces the test sites. Thereafter, it describes the overall nature of the previous termsafetynext term interventions proposed and introduces the methods developed to assess previous termsafety.next term For the previous termtraffic engineeringnext term interventions, positive previous termsafetynext term results were found in terms of reductions in the number of potentially hazardous interactions involving previous termforklifts.next term Similarly, for the vehicle interventions, the research found that previous termforkliftnext term drivers and managers considered the newly developed and installed Intelligent Transport Systems to be broadly acceptable in operational conditions, and the systems’ intended previous termsafetynext term benefits were well understood. The results are discussed and conclusions are drawn regarding human factors aspects of previous termforklift safety.next ter

Safe design of medical equipment: employing usability heuristics to examine the issue of guidewire retention after surgery

Background: Central Venous Catheterisation (CVC) is a medical procedure that has been linked with cases of retained guidewires in a patient after surgery. Whilst this is theoretically a completely avoidable complication, a guidewire of up to 60cm being retained in a patient's vascular system poses a major risk. In recently reported cases, guidewires retained inside patients have not been detected for several years. Aims: The ultimate aim was to develop appropriate, operator-centred safe design solutions that reduce guidewire retention errors. Method: This paper focuses specifically on the application of Nielsen's ten usability heuristics 1 to the issue of retained guidewires. Following the development of a task analysis of the procedure, three researchers (from medical, safety and human factors backgrounds) independently applied the usability heuristics, then met to analyse the findings. Results: A range of usability problems were identified in the Central Venous Catheterisation procedure, and solutions to the identified issues were then proposed: These focused on the design of equipment, or the wider guidewire insertion procedure. The paper details the identified usability problems and possible redesign solutions from the 10 usability heuristics. Conclusion: Overall, the application of the usability heuristics was found to be a useful method both to explore medical device interface problems and to generate possible countermeasures. Further work to eliminate/engineer out the possibility of guidewires being retained is briefly reported

Driver distraction: The effects of concurrent in-vehicle tasks, road environment complexity and age on driving performance

This paper presents the findings of a simulator study that examined the effects of previous termdistractionnext term upon driving performance for previous termdriversnext term in three age groups. There were two in-vehicle distracter tasks: operating the vehicle entertainment system and conducting a simulated hands-free mobile phone conversation. The effect of visual clutter was examined by requiring participants to drive in simple and complex road environments. Overall measures of driving performance were collected, together with responses to roadway hazards and subjective measures of previous termdrivernext term perceived workload. The two in-vehicle previous termdistractionnext term tasks degraded overall driving performance, degraded responses to hazards and increased subjective workload. The performance decrements that occurred as a result of in-vehicle previous termdistractionnext term were observed in both the simple and complex highway environments and for previous termdriversnext term in different age groups. One key difference was that older previous termdriversnext term traveled at lower mean speeds in the complex highway environment compared with younger previous termdrivers.next term The conclusions of the research are that both in-vehicle tasks impaired several aspects of driving performance, with the entertainment system distracter having the greatest negative impact on performance, and that these findings were relatively stable across different previous termdrivernext term age groups and different environmental complexities